Fast, simple ZnO/organic CMOS integrated circuits

Hybrid organic–inorganic CMOS thin-film circuits are a simple, potentially low-cost, approach for large-area, low-power microelectronic applications. We have used atmospheric pressure processes to deposit inorganic ZnO and organic diF TES-ADT semiconductor layers and an Al2O3 gate dielectric. The organic semiconductor uses a contact-treatment-related microstructure that allows circuits to operate without directly patterning the organic layer. Using a simple 4-mask process with bifunctional Ti/Au contacts for both ZnO and organic transistors, 7-stage ring oscillators were fabricated and operated at >500 kHz corresponding to a propagation delay of <150 ns/stage at a supply bias of 35 V. These are the fastest organic–inorganic CMOS circuits reported to date.